Design and analysis of a novel differential Si-based micro-accelerometer based on resonant fork

In order to enhance the sensitivity, stability and to reduce the size of the resonant accelerometers, this paper proposes a novel structure for the resonant Si-based micro-accelerometer. Inertial force of the proof mass is amplified and measured by a one-stage micro-leverage mechanism and a pair of differential double-ended-tuningfork (DETF) resonators respectively. From the natural frequency shift of the DETF, the acceleration can be deduced. Bulk-micromachining can be adopted to manufacture this accelerometer, and the corresponding general manufacturing process is presented. Analytical and finite element analysis (FEA) methods are applied to optimize the sensitive component of the accelerometer; the analytical result is in good agreement with that obtained by FEA method,the FEA sensitivity of the accelerometer is 57.4 Hz/g _n. Results of the analyses show that this proposed accelerometer possesses high sensitivity,high temperature stability and small size.